For the benefit of newbies,I would like to compile a less advance list, concentrating on what and how many image file names allowed in each device to add maps.
Appreciate any feedback in the following format, pls exclude all necessary system files like gmapbmap which is not available to newbies

Bro 168, this information you are seeking is available in older post of MSM thread. You just have to do a "search" for it.
For the benefit of you and others, I have summarize them below :

gmapsupp.img is supplemental mapset ( 1 can reside on Nuvi main memory /garmin and 1 on SD card /garmin )gmapbmap.img is the World basemap ( if loaded ). gmapoem.img, OEM POI data ?? Hard coded, cannot be used by usergmapprom is the Primary mapset that's bundled with the Nuvi, usually the US or Europe map. Resides in PROM1 of Nuvi
( take note that not all Nuvis come with bundled maps )gmapprom1.img is the Secondary mapset that's bundled with the Nuvi ( usually found on units that have both USA and Eurpoe maps preloaded ) Resides in PROM2 of Nuvi

For people who want multiple maps, there are simpler ways as renaming maps with different file names as above is not a cup of tea for most "newbie" or non-technical layman.

One way is to dedicate 1 map to 1 SD ( store them in several "labelled" SD cards for respective countries ). SD cards nowadays are cheap. Most of time you are in 1 country but if you need to move beyond a country border, then change SD card is very siimply done without the need for a SD.

A second way is to combine multiple maps with Mapsource to SD card. This will create ONE gmapsupp.img but it consists of 2 or more maps. Take note that combining too many maps can result in "lag" in the Nuvi ...

Hi Bro SB,
thank you for your detail description on files in Garmin devices, its clear and easily understood.
The purpose of knowing available names for maps is slightly different. Its more for quick practical use.
Newer devices and softwares allow more maps to be stored and used. From the initial rigid gmapoem, gmapprom in equipments, they started to have gmapsupp then gmapsup2 etc.
Some are usable by us, some are not,rather confusing when giving advice.

Just before this thread, I asked for these info, few Sifus told me its not available 'here' but similar info ONLY at 'another place'. One Sifu suggested I table my findings for all's benefit. I felt the same usefulness, hence this thread.

I find renaming files a lot easier than to combine maps using mapsource files etc etc.
and yes I carry extra SDs when abroad, but for testing esp with the various MY maps , I prefer to use GMXT with rename.

SilverBeauty wrote:Bro 168, this information you are seeking is available in older post of MSM thread. You just have to do a "search" for it.
For the benefit of you and others, I have summarize them below :

gmapsupp.img is supplemental mapset ( 1 can reside on Nuvi main memory /garmin and 1 on SD card /garmin )gmapbmap.img is the World basemap ( if loaded ). gmapoem.img, OEM POI data ?? Hard coded, cannot be used by usergmapprom is the Primary mapset that's bundled with the Nuvi, usually the US or Europe map. Resides in PROM1 of Nuvi
( take note that not all Nuvis come with bundled maps )gmapprom1.img is the Secondary mapset that's bundled with the Nuvi ( usually found on units that have both USA and Eurpoe maps preloaded ) Resides in PROM2 of Nuvi

For people who want multiple maps, there are simpler ways as renaming maps with different file names as above is not a cup of tea for most "newbie" or non-technical layman.

One way is to dedicate 1 map to 1 SD ( store them in several "labelled" SD cards for respective countries ). SD cards nowadays are cheap. Most of time you are in 1 country but if you need to move beyond a country border, then change SD card is very siimply done without the need for a SD.

A second way is to combine multiple maps with Mapsource to SD card. This will create ONE gmapsupp.img but it consists of 2 or more maps. Take note that combining too many maps can result in "lag" in the Nuvi ...

Where can I find "gmapbmap.img" in Garmin folder. I dont understand the following guide =>

10. Copy the gmapbmap.img (a free garmin basemap of the world...not much detail just for show) in the install dir (D:\GarminMobilePC\gmapbmap.img)